非线性RLC串联电路中混沌现象的研究

通过回顾混沌现象的历史研究,介绍了混沌的Li-Yoke定义及其特征;分析了非线性RLC串联电路的电路方程和参数.并利用梅利尼科夫(Melnikov)方法推断出非线性RLC串联电路中存在的混沌现象.最后通过计算机模拟结果证实了该方法的有效性.指出采用数值方法求得的李雅普诺夫(Lyapunov)指数存在正指数,这更加说明非线性RLC串联电路中存在着混沌现象.     

N个振荡器相互注入锁定同步振荡系统

本文对Ｎ个振荡器相互注入锁定同步振荡系统提出了一种通用的分析方法。建立了该系统的完整非线性等效模型，导出了系统的状态方程。对于各种不同电路形式的振荡系统，只要将具体的电路参数代入，就可计算其输出功率，功率合成效率及工作频率等参数，从而使这类系统的计算机辅助分析和设计成为可能。     

基于频率响应法的RLC串联电路参数的测量

本文通过频率响应法给出了RLC串联电路参数的测量方法.频率响应与RLC串联电路参数之间呈现非线性关系,通过变量代换得到了线性拟合模型,从而简化了求解过程.基于Multisim的仿真计算结果和基于实际测量的计算结果表明,本文方法作为RLC串联电路参数的测量方法简单可行.     

介观RLC电路在热相干态和热压缩态下的量子涨落

利用热场动力学的方法研究了介观RLC电路在有限温度下的相干态和压缩态中电荷和磁通量的量子涨落.结果表明,介观RLC电路中电荷和磁通量的量子涨落不仅与电路中的元件参数而且可能与环境温度和压缩参数有关,而这些量子涨落与平移参数无关.     

非线性RLC电路的频响特性与稳定性分析

针对非线性RLC电路的频响特性和周期解稳定性等问题,建立了电感非线性RLC串联电路的动力学方程。利用谐波平衡法,导出了电感非线性RLC串联电路的频率响应方程,研究了频率响应特性曲线的跳跃和滞后现象及其不产生谐振现象的条件;分析了该电路周期解的稳定性,得出了稳定区和不稳定区的分界线方程;讨论了非线性因素的影响,得出了忽略RLC串联电路的电感非线性因素的条件。     

谐振电路品质因数的计算

品质因数是谐振电路中一个非常重要的参数,本文讨论了一般RLC电路谐振时品质因数的计算问题,给出了一般RLC电路谐振时品质因数的简单计算方法,即先计算端口的阻抗或导纳,得到等效的串联或并联电路的R、L、C参数,然后套用串、并联谐振电路的品质因数计算公式即可.作者从品质因数的原始定义入手,说明了根据原始定义计算的品质因数与按照本文给出的方法计算的品质因数计算公式是一致的,从而证明了该方法的正确性.     

RLC电路频率响应的计算机辅助分析

应用电子线路仿真软件Multisim对RLC电路的频率响应进行了分析,并讨论了电路参数R,L,C的值变化对频率响应的影响。结果证实:由频率响应曲线精确测量的中心频率f0=3.118 9 kHz和通频带BW=1.591 3 kHz与计算值符合得很好。在RLC电路中,R的数值越小,通频带BW越窄;中心频率f0与电路参数R无关,但随L与C值乘积的减小而增大。实验仿真结果与理论分析是一致的。     

利用OrCAD电路设计软件分析RLC电路频率特性

本文利用OrCAD/Pspice电路设计软件研究RLC串、并联电路中由于参数的改变对电路的频率特性造成的影响。通过软件仿真得到结果 :当中心频率f0=1.59kHz时与通过理论计算的值相近。在RLC电路中,电阻R的值越小,则通频带就越窄;而且中心频率f0的值和电路参数R无关,但当LC的乘积减小时,中心频率f0的值增大。     

电感非线性RLC电路弹簧耦合系统3次超谐共振研究

研究电感非线性RLC电路弹簧耦合系统的非线性振动,应用拉格朗日一麦克斯韦方程,建立受简谐激励的具有电感非线性RLC电路弹簧耦合系统的数学模型.根据非线性振动的多尺度法,得到系统满足3次超谐共振条件的一次近似解以及对应的定常解.对其进行数值计算,分析系统参数对幅频响应曲线的影响.当系统3次超谐共振调谐值等于零时,幅频响应曲线的振幅最大.增大电压、极板面积和非线性电感系数,幅频响应曲线的振幅和共振区增大.增大极板间距、电阻和线性电感系数,幅频响应曲线的振幅和共振区减小.系统的固有频率随极板间距的增大而增大,随极板面积和线性电感系数的增大而减小.     

晶体管电路设计(四)

四、晶体管变频电路关于晶体管变频特性的分析可以采用分析放大特性一样的方法,直接引进一组变频参数,通过这些参数的测量就可以象计算放大电路一样来计算变频增益等;也可以根据晶体管的非线性特性导出一个变频等效电路,再利用它来进行分析计算;而更为直观一些的方法,则可以把晶体管变频电路的作用分成两步来进行分析.首先求出接收信号和本地振荡信号通过晶体管非线性输入阻抗的混频作用,产生了中频     

Resolution Enhancement Technology:Integrated Process Solutions using OPC

DUV lithography, using the 248 nm wavelength, is a viable manufacturing option for devices with features at 130 nm and less. Given the low kl value of the lithography, integrated process development is a necessary method for achieving acceptable process latitude. The application of assist features for rule based OPC requires the simultaneous optimization of the mask, illumination optics and the resist.Described in this paper are the details involved in optimizing each of these aspects for line and space imaging.A reference pitch is first chosen to determine how the optics will be set. The ideal sigma setting is determined by a simple geometrically derived expression. The inner and outer machine settings are determined, in turn,with the simulation of a figure of merit. The maximum value of the response surface of this FOM occurs at the optimal sigma settings. Experimental confirmation of this is shown in the paper.Assist features are used to modify the aerial image of the more isolated images on the mask. The effect that the diffraction of the scattering bars (SBs) has on the image intensity distribution is explained. Rules for determining the size and placement of SBs are also given.Resist is optimized for use with off-axis illumination and assist features. A general explanation of the material' s effect is discussed along with the affect on the through-pitch bias. The paper culminates with the showing of the lithographic results from the fully optimized system.     

Cost-effective test solutions for smart card and other integrated flash applications

From its emergence in the late 1980s as a lower cost alternative to early EEPROM technologies, flash memory has evolved to higher densities and speedsand rapidly growing acceptance in mobile applications.In the process, flash memory devices have placed increased test requirements on manufacturers. Today, as flash device test grows in importance in China, manufacturers face growing pressure for reduced cost-oftest, increased throughput and greater return on investment for test equipment. At the same time, the move to integrated flash packages for contactless smart card applications adds a significant further challenge to manufacturers seeking rapid, low-cost test.     

Theoretical analysis of the relationship between the Brillouin gain coefficient and the strain in the optical-fiber sensors

The relation between the power of the Brillouin signal and the strain is one of the bases of the distributed fiber sensors of temperature and strain. The coefficient of the Bfillouin gain can be changed by the temperature and the strain that will affect the power of the Brillouin scattering. The relation between the change of the Brillouin gain coefficient and the strain is thought to be linear by many researchers. However, it is not always linear based on the theoretical analysis and numerical simulation. Therefore, errors will be caused if the relation between the change of the Brillouin gain coefficient and the strain is regarded as to be linear approximately for measuring the temperature and the strain. For this reason, the influence of the parameters on the Brillouin gain coefficient is proposed through theoretical analysis and numerical simulation.     

An improved parallel thinning algorithm with two subiterations

The parallel thinning algorithm with two subiterations is improved in this paper. By analyzing the notions of connected components and passes, a conclusion is drawn that the number of passes and the number of eight-connected components are equal. Then the expression of the number of eight-connected components is obtained which replaces the old one in the algorithm. And a reserving condition is proposed by experiments, which alleviates the excess deletion where a diagonal line and a beeline intersect. The experimental results demonstrate that the thinned curve is almost located in the middle of the original curve connectivelv with single pixel width and the processing speed is high.     

Novel fiber-optical interferometer with miniaturized probe for in-hole measurements

Today, micro-system technology and the development of new MEMS （Micro-Electro-Mechanical Systems） are emerging rapidly. In order for this development to become a success in the long run, measurement systems have to ensure product quality. Most often, MEMS have to be tested by means of functionality or destructive tests. One reason for this is that there are no suitable systems or sensing probes available which can be used for the measurement of quasi inaccessible features like small holes or cavities. We present a measurement system that could be used for these kinds of measurements. The system combines a fiber optical, miniaturized sensing probe with low-coherence interferometry, so that absolute distance measurements with nanometer accuracy are possible.     

Study of waveguide coupling efficiency in hybrid silicon lasers

This paper presents a new method to increase the waveguide coupling efficiency in hybrid silicon lasers. We find that the propagation constant of the InGaAsP emitting layer can be equal to that of the Si resonant layer through improving the design size of the InP waveguide. The coupling power achieves 42% of the total power in the hybrid lasers when the thickness of the bonding layer is 100 nm. Our result is very close to 50% of the total power reported by Intel when the thickness of the thin bonding layer is less than 5 nm. Therefore, our invariable coupling power technique is simpler than Intel＇s.     

Teleportation of an arbitrary unknown N-qubit entangled state under the controlling of M controllers

A new quantum protocol to teleport an arbitrary unknown N-qubit entangled state from a sender to a fixed receiver under M controllers(M < N) is proposed. The quantum resources required are M non-maximally entangled Greenberger-Home-Zeilinger (GHZ) state and N-M non-maximally entangled Einstein-Podolsky-Rosen (EPR) pairs. The sender performs N generalized Bell-state measurements on the 2N particles. Controllers take M single-particle measurement along x-axis, and the receiver needs to introduce one auxiliary two-level particle to extract quantum information probabilistically with the fidelity unit if controllers cooperate with it.     

Diode-end-pumped Nd:YVO4/LBO lasers with 4.2W continuous-wave output at 457 nm

A continuous-wave (CW) 457 nm blue laser operating at the power of 4.2 W is demonstrated by using a fiber coupled laser diode module pumped Nd: YVO4 and using LBO as the intra-cavity SHG crystal With the optimization of laser cavity and crystal parameters, the laser operates at a very high efficiency. When the pumping power is about 31 W, the output at 457nm reaches 4.2 W, and the optical to optical conversion efficiency is about 13.5% accordingly. The stability of the out putpower is better than 1.2% for 8 h continuously working.     

A rigorous proof of MIMO channel capacity’s increase with antenna number

It is well known that adding more antennas at the transmitter or at the receiver may offer larger channel capacity in the multiple-input multiple-output（MIMO） communication systems. In this letter, a simple proof is presented for the fact that the channel capacity increases with an increase in the number of receiving antennas. The proof is based on the famous capacity formula of Foschini and Gans with matrix theory.     

Call for Papers

正Wireless Body-area Networks The last decade has witnessed the convergence of three giant worlds:electronics,computer science and telecommunications.The next decade should follow this convergence in most of our activities with the generalization of sensor networks.In particular with the progress in medicine,people live longer and the aging of population will push the development of wireless personal networks